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A shorter stiff spring with a helper spring will keep the main spring seated at full droop.

But speaking generally for a track car, you don't need really super long bump travel with stiff rates anyway. Droop is nice. It's still an issue that must be considered though, and more travel is better than too little travel IMO.

- andrew

That's what I was thinking... no doubt droop is nice, but how to achieve it? And there has to be a trade off (besides cost).

Which at full droop would leave the spring flopping around unless we have a long helper spring right?

Yes. Fortunately, the shock absorber can do a hell of a lot on its own. In fact, of the two components - shock and spring - the shock has far, far more control over what's going on than the spring does. The springs really just adjust balance front to rear and limit body roll to an acceptable level. All the dynamic stuff is handled by the shock. That's why things like active shock absorbers are so cool and useful.

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And if the droop was never used during driving, what's the benefit?

Think about it a different way - after a bump, the chassis moves up. If you only have bump travel your wheels are going to come off the ground, even if it's only a little bit. Droop is used after bump. And the droop travel really is used a lot during daily driving.

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I understand you need compression, but is the droop really that necessary for tarmac (non-jumping) use?

Not as much, but yes. How about this - if you're cornering and you have 2" compression on one side and 2" droop on the other you're using 4 inches of travel. Then you hit a bump. Now what? If you only have 4 inches of travel, you're going to go off the road, either through sever overloading of the outside tires or through unsettling the car by suddenly unloading the inside tires.

I did, I don't know the person who shot the video, so if the suspension was soft, then it would be easier to get the droop and travel.

So ultimately, we are saying that almost all of the Japanese coilovers don't offer the performance that the Euro ones offer because of droop travel? Don't get me wrong, I am ok to spend the $2k-$2.5k on new suspension since it's time, but I like that firm feeling and not a lot of body roll. I really don't like the idea of the spring being uncontrolled and unseated if the suspension droops all the way.

So this leaves us with AST, KW v3, what else?

Personally, the dual height adjustable coilover idea is nice since the ride height doesn't change the preload on the spring, and it keeps the spring nice and tight in there. Is there a coilover which can offer the ability to droop and adjust height without changing travel and spring control?

I'm not trying to be a skeptic or argue for the sake of it. I'm just not a suspension pro and my experience is limited to the parts that come to me from people I have relationships with.

I did, I don't know the person who shot the video, so if the suspension was soft, then it would be easier to get the droop and travel.

So ultimately, we are saying that almost all of the Japanese coilovers don't offer the performance that the Euro ones offer because of droop travel? Don't get me wrong, I am ok to spend the $2k-$2.5k on new suspension since it's time, but I like that firm feeling and not a lot of body roll. I really don't like the idea of the spring being uncontrolled and unseated if the suspension droops all the way.

So this leaves us with AST, KW v3, what else?

Personally, the dual height adjustable coilover idea is nice since the ride height doesn't change the preload on the spring, and it keeps the spring nice and tight in there. Is there a coilover which can offer the ability to droop and adjust height without changing travel and spring control?

I'm not trying to be a skeptic or argue for the sake of it. I'm just not a suspension pro and my experience is limited to the parts that come to me from people I have relationships with.

It's williaty's car in the video. It was shot by TIC. If memory serves he was running D-Spec's in that video but I could be wrong.

As pretty much everyone has stated stiffer springs are not going to make droop not needed. Stiffer springs will cause the suspension to not react as well to bumps, possibly lifting a tire in which it will easily cause the shock droop. On the track it's not as big of a deal as normally the track is smoother than roads, but for the average road in the US droop IS important. Stiffer suspension can help compensate for lack of bump travel, but again, this can cause the car to unsettle. I rather have my wheels try and maintain contact with the road at all times rather and F1 it around corners and after hitting bumps and 2 or 3 wheel the car

I can tell you for a fact that my car running 500/400 T2 units easily uses up the entire amount of droop on normal roads.

AST, KW and Ohlins all use helper springs to control preload. I've never unseated a spring and I've had all 4 wheels off the ground before and haven't unseated a spring. The helper spring when compressed doesn't affect the overall spring rate of the unit. It's simply there for when you go into droop that you don't unseat the spring as it will stay preloaded.

It shows a car on a normal road at legal speeds using ALL the bump and droop the stock suspension has. That's about 3x what's even offered by most of the cheap crap coilovers.

Yes, but stock springs and dampers are much softer in comparison to almost all coilovers (not just the BC Racing ones), so it is quite obvious that the wheel will travel more

Leslie

P.S. It has been said many times before, but I'll be happy to repeat, there is more to good suspension then bump travel. Also, ppl should realise that if you want better handling performance, you need to make compromises - and one of the first things that is compromised is comfort.

P.S. It has been said many times before, but I'll be happy to repeat, there is more to good suspension then bump travel. Also, ppl should realise that if you want better handling performance, you need to make compromises - and one of the first things that is compromised is comfort.

I will disagree with bolded section significantly especially on a car that is street driven. My car is pretty damn comfortable to drive in and it's far from stock.

ok what are helper springs? my google searching mostly shows they are used with trucks/suv's to increeeeese the load limit.

Helper springs are springs that are low in rate in comparison to the main springs which take up slack in the suspension before the main springs do their work. In most cases, these helper springs are flat and are compressed most of the time.

Basically, its kind of an aftermarket way of doing what stock springs do with progressive rates. Soft, then stiff as you compress them.

**Experts- correct me if I'm wrong since this is my understanding of how to use them**

It's williaty's car in the video. It was shot by TIC. If memory serves he was running D-Spec's in that video but I could be wrong.

As pretty much everyone has stated stiffer springs are not going to make droop not needed. Stiffer springs will cause the suspension to not react as well to bumps, possibly lifting a tire in which it will easily cause the shock droop. On the track it's not as big of a deal as normally the track is smoother than roads, but for the average road in the US droop IS important. Stiffer suspension can help compensate for lack of bump travel, but again, this can cause the car to unsettle. I rather have my wheels try and maintain contact with the road at all times rather and F1 it around corners and after hitting bumps and 2 or 3 wheel the car

I can tell you for a fact that my car running 500/400 T2 units easily uses up the entire amount of droop on normal roads.

AST, KW and Ohlins all use helper springs to control preload. I've never unseated a spring and I've had all 4 wheels off the ground before and haven't unseated a spring. The helper spring when compressed doesn't affect the overall spring rate of the unit. It's simply there for when you go into droop that you don't unseat the spring as it will stay preloaded.

Ok, so here is the next problem. To get droop and sufficient bump travel, you will need a long spring. In my case, I stuffed a lot of wheel and tire in my fenders and don't have that much room to play with anymore. I noticed that many of the suspension systems that you mentioned seem to have the bottom of the spring below the top of the tire. This simply won't work in my application. Was it an optical illusion or am I really going to be stuck with Japanese coilovers? I want my car to look "cool to the high skool kids", so I don't like the stock ride height. I don't want major fender gap, an inch or so is all I can really handle... I'm stuck huh?

Helper springs are springs that are low in rate in comparison to the main springs which take up slack in the suspension before the main springs do their work. In most cases, these helper springs are flat and are compressed most of the time.

Basically, its kind of an aftermarket way of doing what stock springs do with progressive rates. Soft, then stiff as you compress them.

**Experts- correct me if I'm wrong since this is my understanding of how to use them**

Close. The helper spring doesn't add a progressive rate at all to the system. It's just there to keep the main spring preloaded. 95% of the time it's fully compressed so it's rate in in effect infinte. Some coilovers use progressive main springs though (KW V3's as an example).

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Originally Posted by littlewhitewagon

Ok, so here is the next problem. To get droop and sufficient bump travel, you will need a long spring. In my case, I stuffed a lot of wheel and tire in my fenders and don't have that much room to play with anymore. I noticed that many of the suspension systems that you mentioned seem to have the bottom of the spring below the top of the tire. This simply won't work in my application. Was it an optical illusion or am I really going to be stuck with Japanese coilovers? I want my car to look "cool to the high skool kids", so I don't like the stock ride height. I don't want major fender gap, an inch or so is all I can really handle... I'm stuck huh?

Well, If you are trying to achieve really low ride heights then yes, because the Euro brands don't really offer height independent settings. The AST's and KW's (and therefore RCE units) have quite a bit of room to work with in terms of tire clearance. I've got an ass ton of room between the unit and the wheel and I'm running like -1.3 rear camber. I think boost junkie was running around -1.7- -2 in the rear with a 9.5" wheel at one point and had room on his T2's and his JRZ's.

I will disagree with bolded section significantly especially on a car that is street driven. My car is pretty damn comfortable to drive in and it's far from stock.

Stiffer springs aren't going to change the fact that you need droop.

Agreed
If you count harder bushings- yeah to some extent you'll get increased NVH, but that really to me is NOT NVH, but increased tactile feedback. NVH has a negative connotation, and therefore I only consider NVH unnecessary harshness in a ride. (But that's just my definition)

But remember the biggest cause of NVH on cars is that the struts have been incorrectly matched to springs. So, if your "upgraded" suspension has created lots of NVH, chances are, your struts are incorrectly matched to your springs. Or the damping rates are incorrectly set.

Go-Karts have lots of NVH, but does that mean they have the ideal suspension? No. Now I would also say if you can't feel the road at all, and your ride is super soft, that wouldn't be good either. NVH levels should be at a decent medium where you are able to get tactile feedback from the car without the car being too harsh.

As for droop, how much droop you need is determined by lots of complicated freakin physics things that only Ty understands cause he's a Physics ninja master.
The roughness of the road is one factor, but there's more.
Stuff like body roll, that people try to foolishly get rid of without considering the factors super stiff springs (or in many cases, overly dampened struts) will do to the other parts of the car, is important.
Lowering and stiffening the car is NOT the answer to getting rid of body roll really. What it seems people have a quandary over is the fact that people want to get rid of body roll, and by connection have a snappier car without getting rid of suspension travel. With lowering and super stiff springs, you may lower the center of gravity, and you may have what feels like a stiffer ride, but in reality body roll has more factors than just center of gravity. Something called roll center is a most important factor when it comes to body roll. When you lower the car, you are lowering the roll center, thus making the problems of body roll WORSE, while the stiffer spring rates only mask the real problem. With all of these factors in mind, it is very difficult to get a "perfect setup," but getting close can be done where you can preserve droop and keep roll center high, thus allowing more suspension travel, less body roll, and even sometimes better camber curve. You get a snappier car without a super harsh ride, and you start living life again! Done with theorycrafting. I wish suspension work was as easy as writing stuff.

Also, ppl should realise that if you want better handling performance, you need to make compromises - and one of the first things that is compromised is comfort.

I also strongly disagree with this. A comfortable ride means the chassis is well controlled. Good chassis control translates into better handling and more driver confidence - both make the car faster. I'd say comfort is really the last thing to go, when you go that extra mile to make the car really, really fast. At that point you're in dedicated track car territory.

EDIT: In fact, i've ridden in some extremely soft cars which are horrendously uncomfortable specifically because the chassis is not well controlled.

If that was your point then yes I agree. It seemed like you were trying to make it sound that to have a good handling vehicle it had to be a bear to drive around town.

You still need droop regardless if you're running higher spring rates and higher rated dampers. This idea that spring rate removes the need for travel makes no sense. You want the tire to maintain contact with the road as much as possible and if you don't have travel you're going to start lifting wheels which is going to lower overall grip levels.

I did, I don't know the person who shot the video, so if the suspension was soft, then it would be easier to get the droop and travel.

I would call it medium. Neither terribly stiff nor terribly soft.

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So ultimately, we are saying that almost all of the Japanese coilovers don't offer the performance that the Euro ones offer because of droop travel?

I would say that travel (both droop and bump together) is one of the two biggest reasons the Euro stuff is generally better regarded than the JDM stuff. The other reason being damping.

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Originally Posted by Daishi00

On the track it's not as big of a deal as normally the track is smoother than roads, but for the average road in the US droop IS important.

You'd be surprised how god-awful rough some US tracks are. Not to mention that clipping the kerb to get around another car counts as one big assed bump.

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Originally Posted by littlewhitewagon

Ok, so here is the next problem. To get droop and sufficient bump travel, you will need a long spring. In my case, I stuffed a lot of wheel and tire in my fenders and don't have that much room to play with anymore. I noticed that many of the suspension systems that you mentioned seem to have the bottom of the spring below the top of the tire. This simply won't work in my application.

Well, you've designed yourself into a corner. That happens sometimes. You chose tires over suspension. That may or may not work out for you. That being said, we're able to run 19x10's with our SSTs, so there's go to be a solution.

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I want my car to look "cool to the high skool kids", so I don't like the stock ride height. I don't want major fender gap, an inch or so is all I can really handle... I'm stuck huh?

Again, you've made a design choice that may not be compatible with other design choices. Prioritize.

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Originally Posted by wrxsti.l

Feel free to "want" to disagree, but regardless, you have made a compromise for better handling.

"Pretty damn comfortable" != same comfort as stock, so you have accepted the compromise in comfort, even if it is minor, for better handling and suspension performance - which is what my point was

I have to say that my car is now more comfortable than it was stock and WAY more comfortable than a stock STi. It also handles way the hell better than either. If you do things carefully and with sufficient attention to detail, you can go a long ways before you have to start choosing one over the other.